Large Scale Structure of the Universe

TL;DR

This paper reviews the large-scale structure of the universe, focusing on galaxy clustering, voids, and filaments, and discusses how these observations inform cosmological models and galaxy evolution theories.

Contribution

It provides a comprehensive overview of methods and recent results in measuring and interpreting the universe's large-scale structure, linking observations with theoretical models.

Findings

Galaxy clustering depends on galaxy properties like luminosity and color.

Void and filament structures are quantitatively characterized.

Clustering measurements constrain dark matter halo masses and cosmological parameters.

Abstract

Galaxies are not uniformly distributed in space. On large scales the Universe displays coherent structure, with galaxies residing in groups and clusters on scales of ~1-3 Mpc/h, which lie at the intersections of long filaments of galaxies that are >10 Mpc/h in length. Vast regions of relatively empty space, known as voids, contain very few galaxies and span the volume in between these structures. This observed large scale structure depends both on cosmological parameters and on the formation and evolution of galaxies. Using the two-point correlation function, one can trace the dependence of large scale structure on galaxy properties such as luminosity, color, stellar mass, and track its evolution with redshift. Comparison of the observed galaxy clustering signatures with dark matter simulations allows one to model and understand the clustering of galaxies and their formation and evolution within their parent dark matter halos. Clustering measurements can determine the parent dark matter halo mass of a given galaxy population, connect observed galaxy populations at different epochs, and constrain cosmological parameters and galaxy evolution models. This chapter describes the methods used to measure the two-point correlation function in both redshift and real space, presents the current results of how the clustering amplitude depends on various galaxy properties, and discusses quantitative measurements of the structures of voids and filaments. The interpretation of these results with current theoretical models is also presented.